Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 135/90-15 | 235/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 24.57 (624) | 26.33 (668.7) | 1.76 (44.7) 7.2% |
| Width inches (mm) | 5.31 (135) | 9.25 (235) | 3.94 (100) 74.1% |
| Circum. inches (mm) | 77.18 (1960.35) | 82.71 (2100.78) | 5.53 (140.43) 7.2% |
| Sidewall Height inches (mm) | 4.78 (121.5) | 4.16 (105.75) | -0.62 (-15.75) -13% |
| Revolutions per mile (km) | 820.95 (510.11) | 766.07 (476.01) | -54.88 (-34.1) -6.7% |
235/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.43 mph (34.49 km/h) |
| 25 mph (40.23 km/h) | 26.79 mph (43.12 km/h) |
| 30 mph (48.28 km/h) | 32.15 mph (51.74 km/h) |
| 35 mph (56.33 km/h) | 37.51 mph (60.36 km/h) |
| 40 mph (64.37 km/h) | 42.87 mph (68.99 km/h) |
| 45 mph (72.42 km/h) | 48.22 mph (77.61 km/h) |
| 50 mph (80.47 km/h) | 53.58 mph (86.23 km/h) |
| 55 mph (88.51 km/h) | 58.94 mph (94.85 km/h) |
| 60 mph (96.56 km/h) | 64.3 mph (103.48 km/h) |
| 65 mph (104.61 km/h) | 69.66 mph (112.1 km/h) |
| 70 mph (112.65 km/h) | 75.01 mph (120.72 km/h) |
| 75 mph (120.7 km/h) | 80.37 mph (129.35 km/h) |
| 80 mph (128.75 km/h) | 85.73 mph (137.97 km/h) |
| 85 mph (136.79 km/h) | 91.09 mph (146.59 km/h) |
| 90 mph (144.84 km/h) | 96.45 mph (155.22 km/h) |
| 95 mph (152.89 km/h) | 101.81 mph (163.84 km/h) |
| 100 mph (160.93 km/h) | 107.16 mph (172.46 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1949 | 2265 | 2439 | 2547 | 2663 | 2746 | 2837 | 2945 | 3094 | 3244 | 3410 | 3542 | 3783 | 4048 | 4256 | 4388 | 4463 | 4737 | 5118 | 5948 |
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